Spectra and elliptic flow of light hadrons in an expanding fire-cylinder model for the RHIC Beam Energy Scan

Abstract

We investigate the transverse momentum spectra ($p_T$) and elliptic flow ($v_2$) of ${\pi }^{\pm }$, $K^{\pm }$, $p$, and $\bar{p}$ produced in peripheral Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=7.7$, 11.5, 19.6, 27, and 39 GeV in the Beam Energy Scan (BES) Program at the Relativistic Heavy Ion Collider (RHIC). The analysis is carried out within an expanding elliptic fire-cylinder model that incorporates longitudinal expansion and anisotropic transverse flow. Particle production at kinetic freeze-out is obtained using a local equilibrium distribution function with a blast-wave-like fluid velocity profile derived from the expansion dynamics of the elliptic fire-cylinder. The model parameters governing the collective expansion are first constrained by fitting the midrapidity $p_T$ spectra of ${\pi }^{\pm }$ and are then applied, without further adjustment, to $K^{\pm }$, $p$, and $\bar{p}$. The model provides a consistent description of the $p_T$ spectra and reproduces the qualitative behavior of the elliptic flow for all considered particle species.

(8+4) figures, 5 tables, (14 + 3) pages, accepted in Nuclear Physics A

References in corpus (10)

• Viscosity Information from Relativistic Nuclear Collisions: How Perfect is the Fluid Observed at RHIC?
• Properties of the QCD Matter -- An Experimental Review of Selected Results from RHIC BES Program
• Comprehensive Interpretation of Thermal Dileptons at the SPS
• Pseudo-Critical Enhancement of Thermal Photons in Relativistic Heavy-Ion Collisions
• An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: bulk properties and dynamical evolution
• Blast Wave Fits to Elliptic Flow Data at $\sqrt{s_{\mathrm{NN}}}=$ 7.7--2760 GeV
• Comprehensive simulation of heavy-ion collisions at non-zero baryon chemical potential
• Bayesian Inference of the Specific Shear and Bulk Viscosities of the Quark-Gluon Plasma at Crossover from $\varphi$ and $\Omega$ Observables
• Spheroidal expansion and freeze-out geometry of heavy-ion collisions in the few-GeV energy regime
• Hadron momentum spectra from analytical solutions of relativistic hydrodynamics